﻿/*******************************************************************************************
 * Copyright (c) 2006-2009 Alex Robson, Rob Simmons, Craig Israel, and Rachel Twyford
 *
 * Use of this software in any form requires that you have both 
 * read and agreed to the following terms:
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation 
 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions: 
 *
 * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the 
 * documentation and/or other materials provided with the distribution.
 * Neither the name of Nvigorate nor the names of its contributors may 
 * be used to endorse or promote products derived from this software without 
 * specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 * DISCLAIMED. IN NO EVENT SHALL ANY CONTRIBUTOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ****************************************************************************************/

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;
using Nvigorate.Common;
using Nvigorate.Relational.Mapping.Interface;
using Nvigorate.Extensions;

namespace Nvigorate.Relational.Record
{
    public class ReaderRecord : IRecord
    {
        private int _fieldCount;

        private List<string> _fieldNames = new List<string>();
        private Dictionary<string, int> _fieldIndices = new Dictionary<string, int>();

        private object[] _fieldValues;

        private string _recordSource = "";

        public void Dispose()
        {
            
        }

        public int FieldCount
        {
            get { return _fieldCount; }
        }

        public object this[string fieldName]
        {
            //get { return this[_fieldNames.IndexOf(fieldName)]; }
            get { return this[_fieldIndices[fieldName]]; }
            set { this[_fieldIndices[fieldName]] = value; }
        }

        public object this[int fieldIndex]
        {
            get
            {
                if(fieldIndex > _fieldValues.Length - 1)
                    return null;
                return _fieldValues[fieldIndex];
            }
            set { _fieldValues[fieldIndex] = value; }
        }

        public object this[IAssignmentPoint point]
        {
            get { return this[point.Field]; }
            set { this[point.Field] = value; }
        }

        public List<string> FieldNames
        {
            get { return _fieldNames; }
        }

        public object[] FieldValues
        {
            get { return _fieldValues; }
        }

        public string RecordSource
        {
            get { return _recordSource; }
        }

        public List<string> GetContributingSources(IBindingMap map)
        {
            return new List<string>();
        }

        public Type GetFieldType(string fieldName)
        {
            return this[fieldName].GetType();
        }

        public Type GetFieldType(int fieldIndex)
        {
            return this[fieldIndex].GetType();
        }

        public List<IRecord> GetRelatedRecords(string relationship)
        {
            return new List<IRecord>();
        }

        public IRecord GetRelatedSchemaRecord(string relationship)
        {
            return null;
        }

        public bool HasFieldForAssignment(IAssignmentPoint point)
        {
            return _fieldNames.Contains(point.Field);
        }

        public object GetValueForAssignment(IAssignmentPoint point)
        {
            return this[point];
        }

        public ReaderRecord(IDataReader reader)
        {
            _fieldCount = reader.FieldCount;
            _fieldValues = new object[_fieldCount];
            int index = 0;
            _fieldNames = _fieldValues.Select(v =>
                                                  {
                                                      var name = reader.GetName(index);
                                                      _fieldIndices.Add(name, index++);
                                                      return name;
                                                  }).ToList();
            reader.GetValues(_fieldValues);
        }

        public ReaderRecord(int count, IEnumerable<string> fieldNames, Dictionary<string, int> fieldIndex, object[] values)
        {
            _fieldCount = count;
            int index = 0;
            _fieldNames = fieldNames.ToList();
            _fieldIndices = fieldIndex;
            _fieldValues = values;
        }

        public static IEnumerable<ReaderRecord> GetRecords(IDataReader reader)
        {
            if (!reader.Read())
                return new ReaderRecord[] {};

            var fieldCount = reader.FieldCount;
            int index = 0;
            var throwAway = new object[fieldCount];
            var fieldIndices = new Dictionary<string, int>(fieldCount);
            var fieldNames = throwAway.Select(v =>
                                                  {
                                                      var fieldName = reader.GetName(index);
                                                      if(!fieldIndices.ContainsKey(fieldName))
                                                          fieldIndices.Add(fieldName, index++);
                                                      return fieldName;
                                                  }).ToList();
            List<ReaderRecord> records = new List<ReaderRecord>();
            do
            {
                var fieldValues = new object[fieldCount];
                reader.GetValues(fieldValues);
                records.Add(new ReaderRecord(fieldCount, fieldNames, fieldIndices, fieldValues));
            } while (reader.Read());
            return records;
        }
    }
}
